Configuring PC Lint for uvision & STM32

Transcription

1 Configuring PC Lint for uvision & STM32 David Giles Contents Overview Installing PC Lint Exploring the PC Lint Directory Starting uvision Configuring PC Lint for your project within uvision Running PC Lint Modifying The Behaviour of PC Lint Conclusion Overview PC Lint is a command line tool which will examine and explore your C/C++ source code and provide useful feedback on the syntax, structure and quality of the software that has been parsed. PC Lint can be used with software that has been generated by many of the PC and embedded microcontroller compilers available today. PC Lint is different from most other software checking tools as it does not come with a graphical front end. It is a very simple command line tool that provides a text output. PC Lint can therefore be encompassed into many Integrated Development Environments (IDEs) quite readily by third party tool vendors. One such example of this is uvision IDE by Keil. Pop down menus are included within the standard installation of uvision to run PC Lint. This applications note is targeted at those users wishing to use uvision with the embedded ST Microelectronics target family, STM32, a microcontroller based on the ARM Cortex M3 Core. Install PC Lint Follow the instructions on the PC Lint installation CD. Hitex (UK) Ltd. Page 1

2 Exploring the PC Lint Directory Once the PC Lint tool has been installed check to see if the files have been correctly installed. Below in Fig01 is a screen shot showing Version 8 on PC Lint installed in the C: root directory. Fig01: Screen shot showing PC Lint installed in C: root directory. Starting uvision. Start uvision in the normal way and load up the project you want to check with PC Lint. Hitex (UK) Ltd. Page 2

3 Configuring PC Lint for your project within uvision Once uvision has started, PC Lint can easily be configured. From the Tools menu, select Setup PC Lint. This will pop up a PC-Lint options box. In the Lint Executable select the lint-nt.exe from the c:\lint\ directory. Similarly for the Configuration File select the env-keil.lnt file located in the c:\lint\ directory. Fig2: PC Lint Options The paths for the header files also needs to be added to the PC Lint Include Folders box. These paths may vary depending upon the project you are working with and the compiler you are using to generate the target software. For uvision with the ARM RDK/MDK tools, a lot of the header files are located in the C\Keil\ARM\RV31. These header files relate to the standard generic libraries that are included within most applications such as stdio.h for example. Add this directory to the list of headers. ST provides a set of libraries for use with the STM32. These are used to setup and configure the peripherals on the device. It is a basic Hardware Abstraction Layer library. A copy of these are provided by Keil and included within the installation of the tool chain. If you are using this set of libraries then add this path also to the list of paths in the Include Folders Box. The path for this is C:\Keil\ARM\INC\ST\STM32F10X It may well be that these initial libraries contain errors and you may well have your own later versions of these libraries, which you are using with your code. You may for example have to archive these libraries with your own software and so have moved them to a more suitable location to facilitate this. If this is the case then add this directory location to the Include folders Box instead of the default one used by Keil. All the basic setup is now complete. Close the Include Folders Box. Running PC Lint Highlight one of the source C code files you have within your project and select the Tools Lint option on your file. As the PC Lint tool runs, you will notice a series of messages appear in the Output Window of uvision. Hitex (UK) Ltd. Page 3

4 You will notice there is a fair bit of information generated by the tools. A lot of this may not be of interest to you such as unused variables or functions, as it s likely that many modules of codes provide a library of functions, not all of which are used within the application. The linker will usually remove these for example. If this is the case the PC Lint tool can be modified to exclude certain error or warning codes. Modifying The Behaviour of PC Lint The file that contains the control commands to PC Lint has the extension.lnt and in this example is env-keil.lnt This was the file that was selected during the setup of the PC Lint. You can make a copy of this file, and modify the copy to control the behaviour of PC Lint. Remember to go back to the PC-Lint setup to select the new file name of the lint control file. The standard version of this file contains no error or warning suppression. It s better to keep the original unmodified and to make changes on a copy. Some of the control codes include the following:- The w is used to control the level of warning. These are (from the PC Lint Manual)... -w0 No messages (except for fatal errors) -w1 Error messages only -- no Warnings or Informationals. -w2 Error and Warning messages only -w3 Error, Warning and Informational messages (this is the default) -w4 All messages. An example of a.lnt file is shown below /* env-keil.lnt: environment parameters for Keil's MicroVision IDE From the Tools Menu choose "Setup PC LInt" and follow the instructions provided by Keil We appreciate the assistance of Frank Schmalz in the preparation of this file. */ -hfsb_3 -format="*** LINT: %(%f(%l) %)%t %n: %m" -width(0,10) // Don't break lines (this is required for MicroVision) -w The line w1 has been added into the default.lnt file This will generate only errors and will ignore informationals and warnings. To suppress individual errors simply use the line -e#xxx Where xxx is the error number you want to suppress. The user manual for the PC Lint tool is 300 pages long and details many options for use. Refer to this for more detailed explanation of the lint options. Hitex (UK) Ltd. Page 4

5 Conclusion PC-Lint is very easy to set up and it provides a very useful output report on the quality of the source code written. It can be used during the development of code, to help reduce the probability of coding mistakes. Hitex (UK) Ltd. Page 5